Breaker point adjusting tools



June 20, 1961 sc L E 2,988,939

BREAKER POINT ADJUSTING TOOLS Filed Jan. 26, 1959 I N V EN TOR. JOHN E.SCH/L LER BY ATTORNE Y United States Patent c e 2,988,939 a r I BREAKERPOINT ADJUSTING TOOLS John E. Schiller, 4821 W. Hampton Ave., .5

- Milwaukee, 'Wis; 3 w

Filed Jan. 26, 1959,Ser.No.788,9'18

. 1 Claim. ,(Cl. 81- 3) s 1 This invention relates to tools foradjusting the breaker pointsor contacts of an enginejignition timer ordistributor.

" A type of ignition distributor a breaker point mechaengaged in thenotchand pocket, the screw-driver being then turned to angularlyshiftthe point-carrying plate and thus adjust the gap between thebreaker points. In practice, the use of a screw-driver forthis purposeis generally unsatisfactory since after the desired point gap is setwith the aid of a feeler it is found difficult to hold the screw-driverin fixed position and any inadvertent tipping or shifting of thescrew-driver before or during clamping of the point-carrying plate willresult in changing the gap, making it necessary to repeat the operationuntil the proper gap adjustment is obtained.

An object of the invention is to provide an improved and convenientlymanipulated tool of simple and inexpensive construction which willfacilitate accurate adjustment of breaker points to establish apredetermined gap between them.

Another object is to provide a tool of this character including areadily mounted replaceable end member presenting fulcrum-engaging andnotch-engaging surfaces.

The invention further consists in the several features hereinafterdescribed and claimed.

In the accompanying drawing,

FIG. 1 is an elevational view on an enlarged scale of a breaker pointadjusting tool of the invention, parts being broken away and parts beingshown in section;

FIG. 2 is a bottom end view of the tool;

FIG. 3 is an enlarged fragmentary top view of a breaker point mechanism,showing the tool applied thereto, the tool shank or shaft being shown intransverse section;

FIG. 4 is a fragmentary sectional elevational view taken generally onthe line 4-4 of FIG. 3, and

FIG. 5 is a fragmentary sectional view taken generally on the line 5-5of FIG. 4.

In the drawing, the numeral designates generally a breaker pointadjusting tool of the invention. The tool comprises a shaft or shank 11having at its upper end a handle 12 of any suitable type and having atits lower end a downwardly projecting pivot projection or trunnion 13and a radially projecting finger or blade 14. The pivot projection 13-and blade 14 are preferably formed on a flat insert plate 15 whichsnugly fits in a parallel-sided slot 16 extending diametrically in thelower end of the shank 11 and is suitably secured or clamped therein, asby a cross rivet or screw 17. The slotted lower end of the shank isenlarged to form a cylindrical head 18 coaxial therewith, the headhaving a flat bottom face 19 the plane of which is perpendicular to theaxis of the shank. The lower edge 20 of the insert plate 15 is fiat andcoplanar with the bottom face 19 except for the pivot projection 13which extends downwardly from the face 19 at right Patented June 20,1961 angles thereto. The pivot projection 13 has a rounded orsemi-cylindrical bearing surface 21 at the side thereof remote from thefinger or blade 14, the axis of the hearing surface" being substantiallycoaxial with the tool shank. "In order to cooperate with existingbreaker point mechanisms, one type of which is hereinafter described,the pivot projection or trunnion 13 of the tool is relatively narrow,about 5 inch. To provide adequate strength this projection is made ofoblong cross-section in the plane of theplate, as seen in FIG. 2. Theradial finger or blade 14 extends in the plane of the insert plate andis of outwardly tapered or wedge-shaped cross-section in a plane normalto the axis of the tool, as best seen in FIG 2. The finger or blade isadapted to cooperate with an angularly shiftable point-carrying memberof a breaker point mechanism, as hereinafter described.

3 'In FIGS. 3, '4, and 5, the tool 10 is shown to be applied to a knowntype of ignition distributor 22 which comprises a housing. 23 havingmounted therein an angularly shiftableflistr ibutor plate assembly 24through which a rotary multiple-lobe cam 25 projects. The assembly 24comprises an apertured base plate or disk 26 pivotally mounting thereona point-carrying plate or lever 27. In somednstanc'es, as for an eightcylinder engine, the disk also" mounts thereon a second point-carryingplate 27, shown in broken lines at the left-hand side of FIG. 3. Eachplate 27, which rests flatwise on the disk 26, has secured thereto avertical pivot stud 28 parallel to the cam axis and interengageable withthe disk, as usual, and the plate 27 is adjustably clamped to the diskby one or more screws 29 which pass through slots 30 in the plate andinto threaded openings 31 in the disk. Each plate 27 is provided at anend portion remote from the pivot stud 28 with an upstanding flange orear 32 which rigidly carries a contact or breaker point 33. Anoscillatable spring-loaded arm 34 is pivotally mounted on the pivot stud28 of the plate 27 in insulated relation thereto, and at its free endportion carries a contact or breaker point 35 which cooperates with andis spring-urged against the stationary breaker point 33. A rubbing block36 of nylon or other suitable material secured to the arm 34 isengageable by the rotary cam 25 for periodically separating thearm-carried point from the stationary point. The plate 27 and swingablearm 34 form the usual subassembly which is clamped to the disk 26 by thescrews 29.

The gap between each pair of the breaker points 33 and 35 in their opencondition is adjusted by angularly shifting the point-carrying plate 27about its pivot stud 28, the gap being set by means of a feeler, notshown. A notch 37 is formed in an edge 38 of the plate 27 near thepoint-carrying flange 32, and an opening 39 is formed in the disk 26below the notched portion of the plate. The notch 37 extends radiallywith respect to the pivot stud 28, and the opening 39, which is hereshown to be generally triangular but may be of various other shapes, hasa rounded corner portion or pocket 40 spaced from the notch. Thisconstruction was devised to permit the opposite edges of the blade of ascrew-driver to be engaged in the notch 37 and fulcrum-forming pocket40, the notched pivoted plate 27 being angularly shiftable by turningthe screw-driver, and the plate being thereafter clamped in its adjustedposition.

However, it has been found difficult to effect accurate adjusting of thepoint gap to a predetermined dimension by means of a screw-driver, sincea slight tipping of the screw-driver before or during tightening of thescrews 29 will change the adjustment. Also, in some cases the diskopening 39 is inaccurately punched, making it necessary to use ascrew-driver which is too narrow to properly engage in the plate notch37 and pocket 40. Furthermore, the sharp edges of an ordinaryscrew-driver have a tendency to cut buns in the notch 37 and opening 39.

The tool of the present invention avoids these disadvantages and isapplied by inserting the pivot projection 13 thereof into the diskopening 39 at the pocket 40 and entering .the laterally projectingtapered finger tor .blade 14- :into the tapered plate notch 37, therounded pivoted projection 13 being then seated in the fulcrum-formingpocket 40 of the opening, and the flat bottom face 1-9 -,of the toolhead and insert -plate resting squarely on the flat top face of thedisk. With the plate clamping screws 29 in loosened condition, and withthe rubbing block .36 of the spring-loaded arm on a nose of the rotarycam, a feeler, not shown, of selected thickness held in one hand isinserted between the breaker points, and thedisk-supported tool, whichis held in the other hand, is rotated in one direction or the otheruntil both of the points engage the feeler, the flat bottom face 19 ofthe tool being maintained in flatwise abutment with the disk. The feeleris then removed, and the screws 29 are tightened by a screw-driver whilethe adjusting tool is held in its selected position, insuring the propergap between the points. The breaker points of the other breakersubassembly-are then adjusted in a similar manner to provide the samepoint gap. .11 is noted that the lateral finger 14 of the tool is notrequired to enter the plate opening 39, so that this opening need notextend to the root of the plate notch 37. The cylindrical head 18, fromwhich the finger 14 projects at one side,

is ,of sufficiently small diameter so that it will clear the .nearbycylindrical wall of the distributor housing 23 The distance between theplate notch 37 and the fulcrum-forming pocket 40 of the disk opening maybe different in various breaker plate mechanisms. These variations canbe accommodated by providing the tool with different sizes of insertplates .15.

I claim:

A breaker point adjusting tool, comprising a shaft adapted to be turnedand having a lower ,end portion with a flat bottom face and with adiametrically extending slot, said bottom face being adapted to abutagainst the upper surface of a distributor base plate, an insert plate,fitting in said slot and having .a bottom projection and ,a lateralprojection, and means for rigidly but removably securing said insertplate in said slot, said bottom projection having a lateral bearingsurface remote from said lateral projection and adapted to seatlaterally against a fulcrum surface of the base plate, and said lateralprojection being adapted to engage in a notch of an angularly shit-tablepoint-carrying plate releasably clamped on said base plate.

References Cited in the file of this patent UNITED STATES PATENTS1,424,275 Bates et al. Aug. 1, 1922 1,525,128 Heise Feb. 3, 19252,501,561 Clay Mar. 21, 1950 2,773,529 Valenti Dec. 11, 1956 FOREIGNPATENTS 184,680 Switzerland Aug. 17, .936

